• Toxicological Research
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• v.18 no.4
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• pp.393-396
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• 2002

This study was carried out to evaluate the ostrogenic/antiandrogenic activity of Puerariae Radix in Sprague-Dawley rats. It has known that diverse phytoestrogen were included in some Puerariae Radix, especially in Pueraria mirifica. The Uterotrophic assay and Hershberger assay were performed to evaluate the ostogenic/antiandrogenic activity of various Puerariae Radix (Pueraria thunbergiana, Pueraria mirifica and Butea superba). In Uterotrophic assay, the extracts of Puerariae Radix were administered subcutaneously to immature female SD rats from 19 to 21 days of age. The wet uterus and vaginal weighs significantly increased in the group only treated with extracts of Pueraria mirifica. But, in Hersh-berger assay, all extracts of Puerariae Radix did not show any effects in the castrated rats. These results suggest that Pueraria mirifica has not undrogenic/antiandrogenic effect but potent estrogenic effect. It is possible that components of Pueraria mirifica may act as endocrine disruptor in human body.

• Journal of Environmental Health Sciences
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• v.28 no.4
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• pp.17-22
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• 2002

In crustaceans, as in other arthropods, the molt cycle and the physiological process of growth are controlled by molting hormones (MH) which are steroid hormones, the ecdysteroids. Ecdysteroids are major arthropod hormones which control both development (embryonic and larval molts, metamorphosis) and reproduction. The purpose of the present study was to evaluate both fenarimol and methoprene for embryotoxicity to daphnids. The embryotoxicity associated with each compound was assessed to discern whether the embryotoxicity of methoprene might be due to ecdysone agonist and the ecdysone antagonistic effects of fenarimol on Daphnia embryo. Exposure of daphnids for three weeks to 50 M methoprene resulted in a significantly high incidence of offspring that exhibited general toxicity. This exposure concentration had significant effects on the overall number of embryo death. However, exposure to 3 or 1 $\mu$M fenarimol were no significant effects on the embryo toxicity. The incidence of both of these toxicity increased with methoprene exposure. This observation suggest that methoprene showed embryonic general toxicity during embryo development, while, only fenarimol showed weak general toxicity with early stages of embryonic development.

• Journal of Environmental Health Sciences
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• v.28 no.4
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• pp.1-5
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• 2002

Drosophila Kc cells are ecdysone-responsive : hormone treatment leads rapidly to increased synthesis of several ecdysone-inducible polypeptides (EIPs) and to commitment to eventual proloferative arrest. Later the treated cells undergo morphological transformation, cease to proliferate and to grow. These responses have proven useful as models for studying ecdysone action and environmental endocrine disrupting actions. In this study, we used 20-HE to check out the Kc cells properties to the ecdysone and this properties will be applied to the environmental chemicals to find out the endocrine disrupting action in ecosystem. The cell counts of cultures harvested after 3 days' growth in the presence of 20-hydroxyecdysone. In Kc cell cultures, there were statistically significant different from control cells at 20HE 10/sup 7/-10/sup 5/. The morphological effects of all the hormones were similar, differing only in the dose level at which they were initiated.

• Journal of Environmental Science International
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• v.12 no.1
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• pp.81-86
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• 2003

The study was carried out to evaluate the new analytical method of phthalate esters(diethylphthalate, di-n-butylphthalate, butylbenzylphthalate, bis(2-ethylhexyl)phthalate), one of the endocrine disruptors, which were performed by GC/MS-SIM(selected ion monitoring). The phthalate esters were extracted from water samples using solid-phase extraction on $C_{18}$ columns. It investigated that the extraction recovery rate of phthalate esters with different solvents and solvent volume. The optimal solvent was dichloromethane and proper volume of dichloromethane for recovery of phthalate esters was 4 mL. There were good linearities(above $R^2$=0.9975) in the range 0.01~0.50mg/L, and the detection limits were below 0.01~0.03$\mu\textrm{g}$/L. The recovery rates, RSD and MDLs for phthalate esters were 80~114%, 5.0~8.1% and 0.03~0.11$\mu\textrm{g}$/L, respectively. This method shows a good precision of phthalate esters.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.12
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• pp.1668-1676
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• 2010

The somatotropic axis plays a key role in proliferation and differentiation of avian organs during both pre- and posthatching periods. This review discusses the complexity of regulation of the endocrine system for chicken development and growth by growth hormone (GH), insulin-like growth factor (IGF), and IGF binding protein (IGFBP). In addition, the thyrotropic axis, including thyrotropin-releasing hormone (TRH) and thyroid hormones ($T_4$ and $T_3$), is also involved in the GH-secreting pattern. In mammals, IGFI and -II are always sequestered in a 150 kDa non-covalent ternary complex. This complex consists of one molecule each of IGF-I or IGF-II, IGFBP-3 or IGFBP-5 and an acid labile subunit (ALS). Chick ALS is identified in different strains for the first time, and further investigation of the expression of ALS on developmental stage and ALS effect on IGF bioavailability may be addressed in the future.

• Biomedical Science Letters
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• v.7 no.1
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• pp.27-30
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• 2001

We have examined if lactic acid bacteria could suppress the toxic effect of bisphenol A. Lactobacillus casei YA-70 was chosen as representative. Thirty rats were divided into two groups (immature and mature) according to the weight. Each group was divided again into the control group (only alcohol treatment), bisphenol A treated group, and bisphenol A plus Lactobacillus casei YA-70 treated group. When 500 ppm of bisphenol A was fed everyday, 83% of immature group and 50% of mature group died within 3 weeks. Their internal organs, mainly livers and lungs, were changed in color and severely damaged. In the intestine of 5 ppm-fed group tumor-like nodules were observed. However, their number and size were markedly decreased when Lactobacillus casei YA-70 was supplemented in diet. This study strongly indicates that Lactobacillus casei YA-70 might play an important role to suppress the toxic effect of endocrine disruptor.

• Biomedical Science Letters
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• v.11 no.3
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• pp.333-336
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• 2005

Environmental endocrine disruptors are very toxic to the animals including humans. They are hormone-like acting chemicals which can be found in our normal daily life. We have examined the toxic effect of bisphenol A and if lactic acid bacteria could suppress this toxic effect. Thirty rats were divided into three groups (control, bisphenol A treated, bisphenol A and lactic acid bacteria treated). Treatments were carried out at an interval of 12 hours for each group. Control group showed normal and clear morphology of tissues. Cells were fine in their shape and color, and density was high enough for the normal function. However, bisphenol A treated group was abnormally destructed in cell morphology. In the testis, sperms were totally destructed. When treated with lactic acid bacteria together, the toxic effect of bisphenol A was clearly decreased. This study indicated that bisphenol A was toxic in any concentration especially for the liver and testis, however, lactic acid bacteria could suppress the toxic effects of bisphenol A.

• Asian-Australasian Journal of Animal Sciences
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• v.2 no.1
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• pp.23-26
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• 1989

Treatment of mice with 0.04% anthranilic acid (AnA) as drinking water resulted in an apparent stimulation of pup's growth and food intake of mothers in their first lactations associated with an increased rearing rate and no alteration in plasma prolactin level. AnA showed no significant effects on the day of vaginal opening, the pattern of estrous cycles, plasma growth hormone level and endocrine organ weights of the female and male offspring. The growth of male offspring was significantly retarded by AnA, however, their reproductivity was quite normal. The results indicate the AnA can simulate lactation of mice through little modulation of endocrine systems.

• Clinical and Experimental Pediatrics
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• v.49 no.7
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• pp.718-725
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• 2006

The pubertal activation of gonadotrophin releasing hormone(GnRH) requires coordinated changes in excitatory or inhibitory amino acids, growth factors, and a group of transcriptional regulators. The age of onset of puberty is progressing to younger age. Factors affecting early puberty include genetic traits, nutrition(body fat) and exposure to endocrine disrupting chemicals. In rapidly progressing central precocious puberty, gonadotrophin releasing hormone(GnRH) agonists(GnRHa) appear to increase final height if treated early stage. Further large scaled long-term follow-up study of the effects of GnRHa on final height is needed.

• Clinical and Experimental Pediatrics
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• v.48 no.2
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• pp.126-137
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• 2005

New insights in the complex metabolic pathways and its control mechanism for energy homeostasis have refined our understanding of the pathophysiology of obesity. It is now recognized that there are several additional regulatory mechanism such as peripheral signals including leptin, ghrelin, GLP-1 and PYY and cellular signals including uncoupling proteins and ${\beta}$ Adrenergic receptors, which contribute to the regulation of food intake and energy expenditure, respectively. In addition, the function of adipocyte as an endocrine organ in energy homeostasis has been recently emphasized. Recent findings suggest that elevated levels of adipokines, such as leptin, adiponectin, resistin and TNF-${\alpha}$, in addition to increased free fatty acid level could be related to the pathophysiology of insulin resistance in obesity. For effective treatments and prevention of obesity, further studies on the circuits of neural and endocrine interactions in the regulation of energy homeostasis are needed.